Culturing stromal cells

I started culturing stromal cells from ovarian tissue and I noticed that they have some small black dots inside. Since it's the first time I culture this kind of cell, I have no idea if they are supposed to look like this or it's some sort of contamination. Apart from these black dots inside the cells, everything is normal: medium pH, the cells are well-attached and proliferating, nothing is moving or floating in the bottle... So, I'm totally clueless here. Can anyone tell me what's going on in my culture? Thanks!

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hi there.
Refer to your pic.
is this a primary culture or cell line?
if this is a primary culture, it might be remain residue that attached to the cells.
(note that the 'black' dot are kind like on the the cell mebrane.)
This will be reduce when passaging.
It might be the also protein/liposaccride structure on the cells.
If others parameter(media ph, cell growth, attachment etc) are ok, then it should not be a problem.
If you still worry that might be contamination, jz confirm with bacteria or mycoplasma test.
Cheer

hi there.Refer to your pic.is this a primary culture or cell line?if this is a primary culture, it might be remain residue that attached to the cells. (note that the 'black' dot are kind like on the the cell mebrane.)This will be reduce when passaging.It might be the also protein/liposaccride structure on the cells.If others parameter(media ph, cell growth, attachment etc) are ok, then it should not be a problem.If you still worry that might be contamination, jz confirm with bacteria or mycoplasma test.Cheer

Hi!Thanks for your answer. It's a primary culture and I also thought it could be liposaccharide deposits. I already did four passages and the cells didn't change (same amount of these black dots). So, I was thinking to get some cells for a TEM analysis. But a mycoplasma test could be also nice. Thanks again!